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<h1>Package errors</h1>
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<dd><code>import "errors"</code></dd>
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<p>
Package errors implements functions to manipulate errors.
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<p>Code:</p>
<pre class="code">package errors_test
import (
&#34;fmt&#34;
&#34;time&#34;
)
<span class="comment">// MyError is an error implementation that includes a time and message.</span>
type MyError struct {
When time.Time
What string
}
func (e MyError) Error() string {
return fmt.Sprintf(&#34;%v: %v&#34;, e.When, e.What)
}
func oops() error {
return MyError{
time.Date(1989, 3, 15, 22, 30, 0, 0, time.UTC),
&#34;the file system has gone away&#34;,
}
}
func Example() {
if err := oops(); err != nil {
fmt.Println(err)
}
<span class="comment">// Output: 1989-03-15 22:30:00 +0000 UTC: the file system has gone away</span>
}
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<dd><a href="index.html#New">func New(text string) error</a></dd>
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<a href="http://localhost:6060/src/errors/errors.go">errors.go</a>
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<p>
In the call graph viewer below, each node
is a function belonging to this package
and its children are the functions it
calls&mdash;perhaps dynamically.
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<p>
The root nodes are the entry points of the
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<h2 id="New">func <a href="http://localhost:6060/src/errors/errors.go?s=294:321#L1">New</a></h2>
<pre>func New(text <a href="../builtin/index.html#string">string</a>) <a href="../builtin/index.html#error">error</a></pre>
<p>
New returns an error that formats as the given text.
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<p>Code:</p>
<pre class="code">err := errors.New(&#34;emit macho dwarf: elf header corrupted&#34;)
if err != nil {
fmt.Print(err)
}
<span class="comment"></pre>
<p>Output:</p>
<pre class="output">emit macho dwarf: elf header corrupted
</pre>
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<p class="exampleHeading toggleButton"><span class="text">Example (Errorf)</span></p>
<p>The fmt package&#39;s Errorf function lets us use the package&#39;s formatting
features to create descriptive error messages.
</p>
<p>Code:</p>
<pre class="code">const name, id = &#34;bimmler&#34;, 17
err := fmt.Errorf(&#34;user %q (id %d) not found&#34;, name, id)
if err != nil {
fmt.Print(err)
}
<span class="comment"></pre>
<p>Output:</p>
<pre class="output">user &#34;bimmler&#34; (id 17) not found
</pre>
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